Most existing end-user devices of subscribers in cellular networks are not based on internet-protocol communication standards of packet-switched networks. While some devices are capable of communicating in packet-switched networks, they may roam to other circuit-switched networks outside of the packet-switched network. In order to support access to features of packet-switched networks to subscribers from legacy circuit-based networks and devices, some prior solutions required a call from the subscriber to be anchored into the packet-switched network or support for special capabilities. Since many packet-switched features do not require a bearer channel for their functionality, network resources of both the packet-switched and circuit switched network are wasted when these features are utilized by a subscriber using a legacy circuit-based network or device.
As one example, 3GPP standards have specified a solution to support an interne protocol (IP) multimedia subsystem (IMS) Centralized Services model by using unstructured supplementary service data (USSD) messages as the method for transporting these signals or feature codes to the IMS network. However, 3GPP2 does not support USSD or its equivalent, so not only is there currently no standardized solution for this problem in 3GPP2 markets, but mobiles that support USSD are not widely available in 3GPP markets.
In circuit-switched networks, the configuration of subscriber-modifiable parameters may be accomplished in several different ways, depending upon the particular telecommunications network technology that serves the subscriber. While there are multiple methods for supplementary service interaction, they are generally vendor-specific. For circuit-based subscribers, typically there is a “feature code” or “*” code that can be dialed by the subscriber, and the local switch, during digit analysis, recognizes the * code and handles it appropriately. These “feature codes” and their interpretation are generally vendor specific such as *33 [CallForwardNumber] #, where “*33” is the feature code to change the call forwarding number as indicated. However, maintenance of these dialing plans across multiple regions is operationally problematic and resource intensive.
In the IMS domain for example, there are several innovative features such as WEB-based routing services that can be updated not only from a PC over the internet, but also from IMS enabled UEs. It is currently not feasible for a subscriber to interact with such a service with circuit-based access. While this could be addressed via USSD as specified in 3GPP markets, there is currently no equivalent solution in 3GPP2, and no 3GPP solution when using mobiles that do not support USSD. In general, it is inconvenient or impossible for circuit-based subscribers to avail themselves of these IP-based services using the methods currently available.
Thus, a need exists for a more efficient use of resources for utilization of packet-switched network features.